/*

<This Java Class is part of the jMusic API version 1.5, March 2004.>

Copyright (C) 2000 Andrew Sorensen & Andrew Brown

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or any
later version.

This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

*/

package jm.audio.synth;

import jm.audio.AOException;
import jm.audio.AudioObject;

/**
 * The <bl>Invert</bl> Audio Object is a simple 180 degree phase inverter.
 * any signal that passes through it will be filpped such that all positive
 * values will eb negative and vise versa.
 *
 * @author Andrew brown
 * @version 1.0, March 2003
 */

public final class Invert extends AudioObject {
    //----------------------------------------------
    // Constructors
    //----------------------------------------------

    /**
     * The standard Invert constructor takes a Single
     * Audio Object as input. The audio object
     * passed to it is the prior one in the chain.
     */
    public Invert(AudioObject ao) {
        super(ao, "[Invert]");
    }

    //----------------------------------------------
    // Protected Methods
    //----------------------------------------------

    /**
     * The work method for <bl>Invert<bl> will change
     * the phase of each sample in the buffer.
     */
    public int work(float[] buffer) throws AOException {
        int returned = this.previous[0].nextWork(buffer);
        for (int i = 0; i < returned; i++) {
            buffer[i] = buffer[i] * -1.0f;
        }
        return returned;
    }
}
